Niigata HN130D-BAR

The Niigata HN130D-BAR is where the maker's machining centers overlap most directly with floor-type boring mills. It handles a workpiece of φ3,200 mm × 3,000 mm weighing 8,000 kg (17,637 lb), and its φ130 bar spindle feeds out 555 mm (21.9 in). Yet it remains a pallet machine with a 1,320 mm × 1,320 mm table, an automatic tool changer and a full cover.

That last point is part of Niigata's case for the HN-BAR series. On an open boring mill, coolant and chips go everywhere and the operator works beside the cut. The full cover keeps both inside. The pallet arrangement means an eight-tonne part can be loaded and clocked away from the spindle.

Axis travels are 3,050 mm (120.1 in) in X, 2,050 mm (80.7 in) in Y and 1,420 mm (55.9 in) in Z, with W adding its 555 mm in the Z direction. Traverse is unhurried: 18 m/min in X, 12 m/min in Y and Z, and 5 m/min in W. The pallet indexes at 0.001° as the standard specification on this model, so opposing bores can be aligned by rotating the part with fine angular correction.

The spindle runs to 3,500 min-1 and produces 1,836 N·m (1,354 lb-ft), with BT50 tooling and standard core cooling. The head rides in the centre of a double column on twin Y-axis guides. For tooling, 62 pockets are standard; expandable chain magazines up to 255 tools and matrix magazines up to 230 tools are options. Niigata lists no heavier pallet option for this model.